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"Ectoplasm"Arquivado em 2011-01-11 no Wayback Machine. Glossary of Key Words Frequently Used in Parapsychology, Parapsychological Association (2006-01-24).
"Ectoplasm"Arquivado em 2011-01-11 no Wayback Machine. Glossary of Key Words Frequently Used in Parapsychology, Parapsychological Association (2006-01-24).